If you are thinking of introducing energy saving initiatives, measure how much you're using before you begin.
Unless you know what you are using and what it is costing, you won't know what impact your changes have made. Then keep track of your energy costs, and how they change when you introduce energy-saving measures - if you don't measure it, you don't know if it is working! Measurement can be as simple as just regularly reading the meter, or as complicated as replacing the meter with a smart meter or data logger.